Optical unit, backlight assembly with the optical unit, and display device with the backlight assembly

• US 20080049443A1
• Filed: 07/10/2007
• Published: 02/28/2008
• Est. Priority Date: 08/22/2006
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Philips LCD Company Limited (LG Display Co., Ltd.)
• Inventors: Lee, Jae Young
• Granted Patent: US 7,887,206 B2
• Time in Patent Office: Days
• US Class Current: 362/608
• CPC Class Codes: G02B 6/0023 provided by one optical element, or plurality thereof, placed between the light guide and the light source, or around the light source
• CPC Class Codes: G02B 6/0041 provided in the bulk of the light guide
• CPC Class Codes: G02B 6/005 provided by one optical element, or plurality thereof, placed on the light output side of the light guide

Abstract

An optical includes an optical body including a plurality of side faces where one of the plurality of side faces defines a light entrance face onto which a blue light is incident. A light exit face is connected to at least one of the side faces, and a yellow fluorescent layer is disposed on the light entrance face and is configured to convert the blue light into a white light.

Claims

1. An optical unit comprising:

an optical body including a plurality of side faces having a light entrance face onto which a blue light is incident, and a light exit face connected to the side faces; and

a yellow fluorescent layer disposed on the light entrance face to convert the blue light into a white light.

2. The optical unit according to claim 1, wherein the yellow fluorescent layer includes a first yellow fluorescent portion and a second yellow fluorescent portion.

3. The optical unit according to claim 2, wherein the first yellow fluorescent portion and the second yellow fluorescent portion respectively have a first thickness and a second thickness measured from the light entrance face, the second thickness being larger than the first thickness.

4. The optical unit according to claim 2, wherein the first yellow fluorescent portion and the second yellow fluorescent portion respectively have a first thickness and a second thickness measured from the light entrance face, the second thickness being smaller than the first thickness.

5. The optical unit according to claim 2, wherein the first yellow fluorescent portion has a first area and the second yellow fluorescent portion has a second area smaller than the first area.

6. The optical unit according to claim 2, wherein the first yellow fluorescent portion has a first area and the second yellow fluorescent portion has a second area larger than the first area.

7. The optical unit according to claim 1, further comprising an additional yellow fluorescent layer disposed on the light exit face to convert a portion of the blue light, which leaks onto the light exit face, into white light.

8. The optical unit according to claim 1, wherein the optical body further includes yellow fluorescent beads for converting a portion of the blue light, which leaks onto the light exit face, into white light.

9. The optical unit according to claim 8, wherein the yellow fluorescent beads include a yellow fluorescent material and a binder enclosing the yellow fluorescent material.

10. A display device comprising:

an optical unit including an optical body including a plurality of side faces having a light entrance face onto which a blue light is incident, and a light exit face connected to the side faces, and a yellow fluorescent layer disposed on the light entrance face to convert blue light into white light;

at least one blue light generator unit disposed to provide blue light to the light entrance face;

a receiving case configured to receive the optical unit and the blue light generator unit; and

a display panel disposed to face the light exit face and received in the receiving case to display an image using the white light.

11. The display device according to claim 10, wherein the yellow fluorescent layer facing the blue light generator unit includes a first yellow fluorescent portion and a second yellow fluorescent portion.

12. The display device according to claim 11, wherein the first yellow fluorescent portion and the second yellow fluorescent portion respectively have a first thickness and a second thickness from the light entrance face, the second thickness being larger than the first thickness.

13. The display device according to claim 11, wherein the first yellow fluorescent portion and the second yellow fluorescent portion respectively have a first thickness and a second thickness from the light entrance face, the second thickness being smaller than the first thickness.

14. The display device according to claim 11, wherein the first yellow fluorescent portion has a smaller area than the second yellow fluorescent portion.

15. The display device according to claim 11, wherein the first yellow fluorescent portion has a larger area than the second yellow fluorescent portion.

16. The display device according to claim 10, further comprising an additional yellow fluorescent layer disposed on the light exit face to convert a portion of the blue light, which leaks onto the light exit face, into white light.

17. The display device according to claim 10, wherein the optical body further includes yellow fluorescent beads for converting a portion of the blue light, which leaks onto the light exit face, into white light.

18. The display device according to claim 17, wherein the yellow fluorescent beads include a yellow fluorescent material and a binder enclosing the yellow fluorescent material.